The sceptical scientists I listen to all concede that there might well be an increase in global average temperature of half or one degree Celsius over the next 50 years or so. No one has made a convincing case to my knowledge that huge expenditures to reduce CO2 emissions are justified by that sort of scenario.

It isn't even clear that the warming which appears to be going on is mostly to do with the CO2 emissions because, apart from other explanations for warming, it is not quite clear that the feedback effects resulting from increases in CO2 with its initial greenhouse and therefore warming effect are positive. (They have to be positive and of considerable magnitude to justify the IPCC's scarier projections). How much warming should be expected simply as a result of the ending of the last Little Ice Age (the one which had the Thames frozen in 1804 or 1805)is quite unknown.

Paying ocuntries like Indonesia and Papua New Guinea to presere their rainforest is a good idea anyway. So is research with a realistic chance of producing non polluting processes for energy production, female education in countries where the population growth rate is still high etc.

The most recent complete year figures show a significant increase in Antarctic sea ice cover over the long term average. Northern hemisphere readers are naturally more concerned with what is happening in their half of the world, but 90% of the world's ice is locked up in Antarctica and changes there are what have the greatest effect on world ice volumes. For all there sensationalist headlines, it pays to keep a cool head, as do the penguins.

"the resulting open sea means that there is additional phytoplankton that will absorb the equivalent CO2 as 60 to 170 square kilometres of rain forest, or 0.0004% of the CO2 produced from fossil fuels and deforestation"

"As soon as we detect "bias" by the reporters or scientists, we tend to disbelieve both sides."

Exactly. So if you run a profitable industry that is threatened by scientific discoveries about negative side-effects, what do you do? You try to create confusion.

Here's some useful tactics:
* 1. Allege that there's a conspiracy. Claim that scientific consensus has arisen through collusion rather than the accumulation of evidence.
* 2. Use fake experts to support your story. "Denial always starts with a cadre of pseudo-experts with some credentials that create a facade of credibility," says Seth Kalichman of the University of Connecticut.
* 3. Cherry-pick the evidence: trumpet whatever appears to support your case and ignore or rubbish the rest. Carry on trotting out supportive evidence even after it has been discredited.
* 4. Create impossible standards for your opponents. Claim that the existing evidence is not good enough and demand more. If your opponent comes up with evidence you have demanded, move the goalposts.
* 5. Use logical fallacies. Hitler opposed smoking, so anti-smoking measures are Nazi. Deliberately misrepresent the scientific consensus and then knock down your straw man.
* 6. Manufacture doubt. Falsely portray scientists as so divided that basing policy on their advice would be premature. Insist "both sides" must be heard and cry censorship when "dissenting" arguments or experts are rejected.

If you are confused but care, the answer is not to give up, but to seek information. If you don't trust all the leftish-green sites, try NASA (http://climate.nasa.gov/), which can hardly be accused of being on the radical green fringe.

This says that:
"Over the last 50 years, around 24,000 square kilometres of new open water have been created" ... "by the recent, rapid melting of several ice shelves - vast floating plaques of ice attached to the shore of the Antarctic peninsula".

"Ice shelves are ledges of thick ice that float on the sea and are attached to the land. They are formed when ice is exuded from glaciers on the land. In the past 20 years, Antarctica has lost seven ice shelves."

(It points out that the resulting open sea means that there is additional phytoplankton that will absorb the equivalent CO2 as 60 to 170 square kilometres of rain forest, or 0.0004% of the CO2 produced from fossil fuels and deforestation.)

Of course, it gets even better if we only look at the area within 100 km of the north pole. Or even 1 km. There, the reduction in ice cover so far has been 0%! We can all feel great relief that we don't have to change our very way of life to reduce our greenhouse gas production, because if we choose our parameters such that they don't pick up any changes, everything looks normal! Isn't that great? Have a careless summer!

(With apologies to AlterEggo, who probably thinks I've used up my alotted number of postings, but I couldn't resist this one. I am allergic to logical fallacies.)

The National Snow and Ice Data Center (NSIDC) is confusing us all which should be stressed in an article like this. How many of you think that countries like Germany or Japan belong to the Arctic? Quite few I guess but the NSIDC does! When they use the word "Arctic ice" they in fact mean "northern hemisphere ice". The observant reader notes this from the peculiar fact that the sea ice maximum occurs already in March. In the true Arctic little melting takes place before May. Their most unusual definition of the Arctic is, surprisingly, not mentioned anywhere - a mail conversation which required more than a simple reply was necessary to confirm that they do indeed measure northern hemisphere ice which thus include the entire Baltic Sea and the northern Pacific (where winter ice occurs all the way down to Hokkaido). I don't think there exist an absolute definition of the Arctic but using either the Arctic circle or the extent of Arctic climate (warmest month cooler than 10 C) would be much more reasonable.
Using the "super Arctic" definition does not have any importance as to the ice minimum since ice can only survive the summer in the true Arctic. It does, however, greatly influence the importance of summer melting. In the true Arctic summer melt is far less dramatic probably leading to less than 50% summer shrinking compared to the almost 75% in the NSIDC figures. Why this strange definition of the Arctic is used and why it is not clearly stated is a puzzle to me. It is, however, very unfortunate in the already very infected climate issue. It could be interpreted as an attempt of dramatization of a perfectly normal but wonderful phenomenon - the advent of summer!

There is also Mount Kilimanjaro, which has lost almpst half its icecap. Thirty years ago it had a beautiful snowcap. Now it has snow on the top only; all else is barren due to there not being any water for vegetation.

Atlantic Conveyor: This is where dense cold arctic waters which are highly saline mix with the warm waters of the Gulf Steam. Actually they do not mix that much or exchange ions, but the heavier saline waters sink and become the return for the Gulf Stream.

@Macumazan,
"What is clear is that the models don't work."
GCMs do work. Check your facts:
"We use the GISS global climate model to make a preliminary estimate of Mount Pinatubo's climate impact. Assuming the aerosol optical depth is nearly twice as great as for the 1982 El Chichon eruption, the model forecasts a dramatic but temporary break in recent global warming trends. The simulations indicate that Pinatubo occurred too late in the year to prevent 1991 from becoming one of the warmest years in instrumental records, but intense aerosol cooling is predicted to begin late in 1991 and to maximize late in 1992. The predicted cooling is sufficiently large that by mid 1992 it should even overwhelm global warming associated with an El Nino that appears to be developing, but the El Nino could shift the time of minimum global temperature into 1993. The model predicts a return to record warm levels in the later 1990s. We estimate the effect of the predicted global cooling on such practical matters as the severity of the coming Soviet winter and the dates of cherry blossoming next spring, and discuss caveats which must accompany these preliminary simulations." [1]
More on models here [2]

"The same is true with public policy where wrong predictions in the area will cause policy changes costing us trillions."
You're quick to blame geophysical models. However, you show no reservations about the predictions of a handful of economic models about the cost/benefit of climate policy. Your ideological blinders force you to accept double standards on modelling.

"It might be that total World wide ice cover is actually increasing"
Err, no [3]. Only the East Antarctica ice sheet is considered to be stable (although recent papers are questioning this). Arctic sea ice, the West Antarctica and Greenland ice sheets and the overwhelming majority of glaciers are losing mass. The growth of Antarctic sea ice is consistent with global warming [4]

"Certainly the recent decade of plateaued temperature flies in the face of what the models predicted"
- Stagnant global temperatures? Not so much:
"The combined global land and ocean surface temperature was the warmest on record for May, March-May (Northern Hemisphere spring-Southern Hemisphere autumn), and the period January-May according to NOAA. Worldwide average land surface temperature for May and March-May was the warmest on record while the global ocean surface temperatures for both May and March-May were second warmest on record, behind 1998." [5]
- Not predicted by models? You're wrong [6]

@Sense Seeker,
"I wonder whether this might have consequences for ocean currents. If the Gulf Stream stops, Europe will experience another ice age."
Two things:
- The contribution of the Gulf Stream to Europe's relatively mild climate is minimal [7]
- Evidence and models predict a slight weakening of the North Atlantic drift on this century, not a shutdown [8]

Wow, quoting Wikipedia as a reference....Just as the Austrailian magazine can have an opinion, the authors of Wiki are certainly unflitered and can say what they want. Just ask GW Bush...

My beef with the ice melting crowd is that there is never any discussion of the mass added to the ice pack. Area is misleading: the ice can be 1 m thick or 1000 m think, yet is counted the same in the stat.

There has to be mass added: the CO2 research has made numerous holes in the ice pack, correlating a CO2 value with a layer from each year. Where is the ice addition data presented?

Same news, different source: "Reporting in the journal Geophysical Research Letters, scientists from British Antarctic Survey (BAS) and NASA say that while there has been a dramatic loss of Arctic sea ice, Antarctic sea ice has increased by a small amount as a result of the ozone hole delaying the impact of greenhouse gas increases on the climate of the continent."
(http://www.sciencedaily.com/releases/2009/04/090421101629.htm)

Sense Seeker writes "I am not aware of any model that predicts when the Gulf Stream might shut down."
The ancient Gauls were afraid of the sky falling on them, but that eventuality is also not sustained by physical models. The absence of models for both events should be a great relief to us all.

My post said: "The following newspaper article REFERENCES reputable sources ..." meaning that the sources to check were the ones mentioned in the article; not the newspaper article itself. "The Australian" is the antipodean equivalent of the London Times, both of which are Murdoch owned and that share common articles. If anything, it suffers from the same pro-alarmist global warming editorial tilt as does the "Times", but it is certainly reputable in its articles. Anyway, perhaps you might care to specifiy which of the learned bodies referred to in the article were misquoted.

The Australian is not a reliable source on issues of climate change, I am afraid. That newspaper runs an active campaign to discredit the whole idea, selectively cites the evidence and experts, etc.

According to wikipedia (which cites scientific peer-reviewed publications), recent studies suggest the East Antarctic Ice Sheet was in balance but the West Antarctic Ice Sheet was losing mass. That does not support your theory that if ice is lost on one end of the globe, it is added to the other.

I am not aware of any model that predicts when the Gulf Stream might shut down. I am just worry that it might, and that if it happens, that it will have disastrous consequences. As far as I know, it is driven by waters cooling in the arctic, then descend because cold water is more compact, and move over the ocean floor away from the pole. If there is less ice at the pole, less circulation might logically result. But I'm happy to be proven wrong on this one.

The following newspaper article references reputable sources that Antarctic ice cover is expanding. Given that Arctic cover is decreasing, the only question that matters is the numerical magnitude of the rates. Pending further evidence, I'm happy that "roughly constant" is correct. It might be that total World wide ice cover is actually increasing, but I did not venture that, nor did I point out the recent retraction of the nonsense about melting of the Himalayan ice in thirty years, which retraction, of course, significantly helps my case. In any case, I have 'backed it up".

On the models, the problem is that they do not work retroactively. and, as with stock market predictions, their predictive power is not good, though they can fraudulently be made to look good with post facto adjustments. In short, we do not HAVE climate models with predictive power. Certainly the recent decade of plateaued temperature flies in the face of what the models predicted. it is clear that they are not sufficiently stout to bear the weight that a tax of 10% or more of world industrial production would need to be supported by.

On the Gulf Stream shutting down, can you tell us precisely what the time frame is that the models predict this will happen in, and what time frame its NOT occurring in would suffice to shake your faith in the models?

On Arctic navigation, of course, any predictive aid is a good thing, provided it is genuinely predictive. Exactly how well have, say the 1999 climate models furthered current navigational advice to mariners?